Locking mechanism



April 21, 1970 R. c. DELLERT LOCKING. MECHANISM Filed Aug. 1. 1967 2L4 FIGA Fl INVENTOR ROBERT C. DELLERT United States Patent 3,508,043 LOCKING MECHANISM Robert C. Dellert, Bloomington, Ill., assignor to General Electric Company, a corporation of New York Filed Aug. 1, 1967, Ser. No. 657,690 Int. Cl. F21v 21/08 US. Cl. 24052.1 11 Claims ABSTRACT OF THE DISCLOSURE v A mechanism for locking a stationary indicator unit or a reciprocative illuminated push button unit withm a cavity in a panel mounted housing. A cantilevered leaf spring which includes a portion extending into the housing cavity having a shoulder formed therein, is

BACKGROUND OF THE INVENTION Stationary indicator units or 'recip rocative push button units are received in the cavity of a housing which is secured in an aperture in a panel. Electrical translating devices such as lamps may be mounted in the units. It is desirable that a unit be removably retained in the housing cavity, such that it will not be displaced from the cavity by jarring or by vibration of the panel, but such that it may be easily removed from the housing cavity so as to provide access to the translating devices mounted therein. In the past the units have been retained in the housing cavity by a pair of springs, mounted on opposite sides of the housing, which engaged opposite sides of the unit. However, difliculty was experienced in forming and mounting the pair of springs so as to provide enough force to retain the unit in the housing cavity and yet not so great a force as to make it extremely difficult to remove the units from the housing cavity.

OBJECTS OF THE INVENTION SUMMARY OF THE INVENTION The foregoing objects are accomplished in accordance with this invention when a preferred embodiment is utilized with a housing or receptacle part having a cavity therein for receiving an insertable part such as a stationary or reciprocative unit or member. In the preferred embodiment the mechanism includes a spring means, a

first portion of which is secured to a side wall of the housing so as to support in a cantilever manner a second portion which extends into the cavity, and a third portion which includes a cam portion extending from the free end of the second portion toward the side wall upon which the first portion is secured. A shoulder is provided on the second portion of the spring means to 3,508,043 Patented Apr. 21, 1970 ICC engage an engaging means which is a shoulder formed on the member received in the cavity, the engagement of the shoulders retaining the member in the housing. The mechanism further includes a stop means movably mounted on the same side wall of the housing as is the spring means to permit relative movement of the stop means and the spring means. In a first position the stop means engages the free end of the third portion of the spring means to support the third portion of the spring means as a simple beam such that it is incapable of being deflected to the extent necessary to permt removal of the member received in the cavity. In a second position the stop means does not engage the spring means, such that the third portion of the spring means is supported in a cantilevered manner and may be easily deflected to the extent necessary to disengage the shoulders such that the member received in the cavity may be removed.

BRIEF DESCRIPTION OF THE DRAWINGS FIGURE 1 is a perspective view of a housing having a light box secured therein by the improved locking means contemplated by this invention.

FIGURE 2 is a perspective view of the housing and light box with the light box shown external to the housing 'in position to be inserted in the housing.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the perspective views shown in FIGURES 1 and 2, one embodiment of the locking mechanism as utilized in an indicating light assembly will be described. The indicating light assembly includes a housing assembly 10 and a light box or lens assembly 12 which is received within a cavity in the housing assembly. The housing assembly 10 includes a generally rectangular housing or receptacle 14 formed of an insulating material with side walls 16, end walls 18, a first open end 20 and a second closed end or base 22. The lens assembly 12 which is received in the housing 14 through the open end 20 includes a hollow generally rectangular insulating member 24 over the open outer end of which is secured a light transmitting lens cap 25. The insulating member 24 is formed with an inner end or base 26 upon which are supported one or more electrical translating devices such as electrical lamps 27 which are energized from an electrical source through electrical connecting means including terminals 28 which extend through the base 22 of the housing 14. Electrical connections are made between the lamp contacts and the terminals 28 by resilient connectors such as rivets 29 biased by coil springs 31.

The housing assembly 10 is secured in a rectangular aperture in a panel 30 as shown in FIGURE 6 by the engagement of a flange 32 provided around the open end 20 of the housing 14 and arms 34 of a pair of spring members or retaining clips 36 with opposite sides of the panel. The retaining clips 36 are secured to the side walls 16 of the housing by mushrooming projections 38 formed integrally with the side walls 16 of the housing over holes provided in .the retaining clips 36.

In accord with the invention an improved means is provided for positively locking the lens assembly 12 in the housing assembly 10. The locking mechanism comprises cooperating relatively movable stop and spring means arranged such that when in first relative positions of engagement, they effect locking of the assembly 12, and when in second relative positions of disengagement, they release the assembly 12 for removal. In the preferred form the stop is movable relative to the spring to effect the locking and releasing functions. According to the specific embodiment illustrated, the locking mechanism includes two principal elements in the form of a spring member 40 which is best seen in FIGURES 4-7 and a stop 42 which is shown in all of the figures, and in an enlarged view in FIGURE 3. The spring member 40 and the stop 42 are preferably secured to a side wall 16 of the housing 14 over a slot 44 formed in the side wall. The slot 44 which is generally rectangular in shape is separated into two parts by a cross member 46.

The first principal element of the locking mechanism, spring member 40, which preferably is a leaf spring, includes a first or base portion 48 which is provided with a pair of tabs 50 and 52 which extend at right angles into apertures 54 and 56, respectively, in side wall 16 of the housing 14. As is best seen in FIGURES and 7, the base portion 48 of spring member 4'0 is secured between side wall 16 and retaining clip 36 to be retained in position. Extending from the base portion 48 of spring member 40 is a second portion or a first arm 58 which extends through a first part of the slot 44 into the cavity in the housing 14. The free end of first arm 58 is bent at approximately right angles to base portion 48 .to form a shoulder 60 facing the base 22 of the housing 14. Extending from the shoulder 60 is a third portion or second arm 62 which extends outwardly from the cavity toward the side wall 16 of the housing and terminates in a curved tip 64.

The engaging means provided on the insulating member 24 of the lens assembly 12 for receiving shoulder 60 of spring member 40 includes an aperture 66. The lower edge of aperture 66 is provided with a recessed cam surface 68 which extends from the base 26 and terminates in a shoulder 70 which faces the open end 20 of the housing 14 and which is engaged by the shoulder 60 of spring member 40.

The second principal element of the locking mechanism, stop 42, includes a generally rectangular body portion 72 and first extending portions such as pairs of arms 74, 76, and second extending portions such as pairs of arms 78 which serve to secure the stop in the slot 44 in the housing. As shown by the dashed lines 80 in FIG- URE 4, channels are provided on the inner surface on the side wall 16 on each side of slot 44 for receiving the pairs of arms 74 and 76. Similarly, as also shown in FIGURE 4, channels 82 are provided on the outer surface of side wall 16 on each side of slot 44 to receive the pair of arms 78. The bases of channels 82 are provided with a pair of aligned rounded projections 84 and 86 which coacts with pairs of arms 78 to define two positions of stop 42 and to serve as detents to maintain the stop 42 in either of the two positions. A tab 88 is provided on stop 42 to facilitate movement of the stop 42 between its two positions, one of which is shown in FIGURES 1, 6, and 7, and the other of which is shown in FIGURES 2, 4, and 5.

Referring first to FIGURES 2, 4, and 5, the operation of the locking mechanism will now be described. The lens assembly 12 may be inserted in the housing 14 with the stop 42 in either of its two positions. With the stop in the raised position shown in FIGURES 2, 4, and 5, lower portion 90 of the stop does not engage the curved tip 64 of spring member 40. Thus, upon inserting lens assembly 12 into housing 14, cam portion 68 of insulating member 24 will engage the inner surface of second arm 62 of spring member 40 which serves as a cam portion and deflect it outwardly into the first portion of slot 44. As shoulder 70 of the insulating member 24 passes by shoulder 60 of the spring member 40, the spring member will move inwardly under its own force, to cause engagement of shoulders 60 and 70.

If the stop means was as presupposed in the position shown in FIGUIES 2, 4, and 5, it may now be depressed to the position shown in FIGURES l, 6, and 7 whereupon cam 92 at the lower edge of lower portion of stop 42 will engage curved tip 64 of the spring member 40 to inwardly deflect second arm 62 such that the curved tip 64 engages the flat inside surface of the stop 42. With the stop in the position shown in FIGURES 1, 6, and 7, the spring member 40 is supported at each end as a simple beam, such that it will not deflect outwardly to permit withdrawal of the lens assembly 12, and will re tain the lens assembly 12 in the housing 14 against the force of spring 94 shown in FIGURE 7.

Should it be desirable to withdraw the lens assembly from the housing 14, for instance, to replace the lamps mounted on the base 26 thereof, a force is applied to tab 88 to raise the stop 42 to the position shown in FIG URES 2, 4, and 5. With the stop 42 in this position the spring member 40 is supported only by its base portion 48, such that its second arm 62 is easily deflected outwardly as shoulder 70 of insulating member 24 is pulled outwardly with relatively little force against shoulder 60 of spring member 40. The outward deflection of the spring member 40 disengages the shoulders 60 and 70 such that the lens a sembly 12 may be easily removed from the housing 14. p t

The lens assembly 12 may also be inserted into the housing 14 when the stop 42 is in the position shown in FIGURES 1, 6, and 7. While a greater force must be applied to the lens assembly 12 to insert it in this manner, the engagement of the cam portion 68 of the insulating member 24 with second arm 62 of the spring member 40 will cause the shoulder 60 of the spring member to be deflected outwardly such that shoulder 70 of the insulating member 24 may be moved below it, whereupon shoulder 60 will snap over shoulder 70 to retain the lens assembly 12 in the housing 14.

The member 24 may be a stationary indicator unit or a reciprocative illuminated push button unit depending upon the spacing between base 22 of the housing 14 and base 26 of the member 24 when the member is locked in the housing 14 as shown in FIGURES 1, 6, and 7. If no spacing is provided, a stationary indicator unit is provided. However, if spacing is provided it should be noted that the locking mechanism prevents only outward movement of the member 24, and that member 24 may -be depressed inwardly until the top edge of aperture 66 engages the second arm 62 of the spring member 40. Thus with the spacing provided, an actuating member can be provided on the base 26 of the member -14 which will pass through an aperture in base 22 of the housing 14 to actuate the mechanism such as a switch attached to the outer surface of the base 22.

While a particular embodiment of this invention has been shown and described, it will be obvious to those skilled in the art that various changes and modifications may be made without departing from this invention in its broader aspects and, therefore, it is intended that the appended claims cover all such changes and modifications as fall within the true spirit and scope of this invention.

I claim:

1. A locking mechanism comprising in combination:

(a) a receptacle part having side walls and an open end;

(b) an insertable part removably mounted in said receptacle part and being installed and removed relative to said open end;

(c) a leaf spring on said receptacle part having a portion positioned for detaining engagement with said insertable part when said insertable part is installed, said spring having a free end and being deflectable to move said portion of said spring into and out of detaining engagement with said insertable part;

(d) a stop on said receptacle part; and

(e) means for effecting relative movement between said spring and said stop when said insertable part is installed between a first relative locking position wherein said stop engages said free end of said spring, and a second relative releasing position wherein said stop is disengaged from said spring, said spring when in engagement with said stop being supported as a simple beam to prevent deflection of said spring whereby said portion of said spring engages said insertable part to prevent removal of said insertable part, and said spring when disengaged from said stop being supported as a cantilever beam to premit deflection of said spring and disengagement of said portion of said spring from said insertable part whereby said insertable part can be removed from said receptacle part.

2. A mechanism as defined in claim 1 wherein said relative movement between said spring and said stop is along an axis generally parallel to the axis of movement of said insertable part relative to said receptacle part during installation and removal of said insertable part.

3. The locking mechanism defined in claim 1 wherein said second end of said receptacle part is closed and said receptacle part and said second end are formed of an insulating material, said insertable part is formed of an insulating material, and comprising in addition (a) at least one electrical translating device supported by said insertable part,

(b) at least one electrical connecting means supported by said receptacle part, said electrical connecting means being electrically connected to said electrical translating device when said insertable part is locked in said receptacle part.

4. The locking mechanism defined in claim 1 wherein said insertable part is formed with side walls, and a light transmitting outer end, and an inner end which supports said electrical translating device which are electrical lamps.

5. A locking mechanism comprising in combination:

(a) a receptacle having side walls, a first open end, and

a second end,

(b) a member removably received within said receptacle through said first open end,

(c) a spring means supported on the side wall of said receptacle having at least three portions,

(i) a first portion supported on the side Wall of said receptacle,

(ii) a second portion supported by said first portion extending within said receptacle away from the side wall,

(iii) a third portion supported by said second portion extending from within said receptacle toward the side wall,

(d) engaging means provided on said member to be engaged by said second portion of said spring means when said member is received within said receptacle and (e) a stop means mounted on the side Wall of said receptacle movable to at least two positions,

(i) a first position wherein said stop means engages said third portion of said spring means to limit deflection of said spring means so as to lock said member in said receptacle,

(ii) a second position wherein said stop means does not engage said third potrion of said spring means, such that said spring means may deflect to permit withdrawal of said member from said receptacle.

6. The locking mechanism defined in claim 5 wherein said second portion of said spring means is provided with a shoulder facing said second end of said receptacle, and said engaging means provided on said member is a shoulder which faces said first open end of said receptacle when said member is received within said receptacle, and said shoulder on said spring means engages said shoulder on said member, such that when said stop means is in the first position said member is locked in said receptacle by the engagement of said shoulders.

7. The locking mechanism defined in claim 5 wherein said third portion of said spring means includes a cam portion which engages said engaging means on said member to permit insertion of said member in said receptacle with said stop means in any position.

8. The locking mechanism defined in claim :5 wherein a slot is provided in a side wall of said receptacle, and said first portion of said spring means is supported on the outer surface of said side wall of said receptacle, and said second portion extends through said slot to within said receptacle.

9. The locking mechanism defined in claim 5 wherein a slot is provided in a side wall of said receptacle, and said stop means is slidable supported in said slot.

10. The locking mechanism defined in claim 9 wherein said stop means is provided with a first extending portion for engaging the inside surface of said walls of said receptacle and a second extending portion for engaging the outside surface of said side walls of said receptacle so as to maintain said stop means in said slot.

11. The locking mechanism defined in claim 9 wherein said first portion of said spring is supported on the outer surface of said side wall of said receptacle, and said second portion extends through said slot to within said receptacle.

References Cited UNITED STATES PATENTS 2,784,987 3/1957 Corcoran 295-87 2,904,662 9/1959 Spring 200-167 3,157,771 11/1964 Roeser 200-167 3,246,320 4/ 1966 Houbolt 340-381 NORTON ANSHER, Primary Examiner F. L. BRAUN, Assistant Examiner U.S. Cl. X.R. 200-167; 240-151; 340-381 mg UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION- Petent No. 3,508,043 Dated April 21, 1970 Inventofl Robert g Qellert It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 5, line 32, the claim reference numeral "1" should read 3 Column 6, line 5, the word "potrion" should read portion SIGNED AND sumo Ave 4 Z 'l dominion of hue" 

